Unifor's contract with Ford Motor Co. is set to expire at 11:59 p.m. ET tonight.
The union is negotiating with Ford in hopes of reaching an agreement that can be used as a blueprint for workers at General Motors and Stellantis.
Unifor has said it is focused on improving pensions, increasing wages and securing good jobs in a future set to be dominated by electric vehicles.
Unifor members at Ford have voted 98.9 per cent in favour of a strike if the bargaining committee fails to secure a new collective agreement.
The talks continue as autoworkers represented by the United Auto Workers in the United States are on the picket line.
Some 13,000 U.S. autoworkers started striking last week, targeting a plant at each of the Detroit Three automakers.